Chicago Storm

0z UKMET stayed south.

0z GFS is literally a further north copy of the weekend storm.

0z GGEM actually came north. Way farther north than any other 0z guidance so far. SLP travels through far S. Illinois.

0z GFS going to be terrible everywhere.

12z GFS is coming in further south with the southern wave, and slower with the northern wave. That delays any possible phase till after it's past the region. In other words, not good for the Chicago crew...as it leads to a further south/weaker solution. Edit: This run also digs the southern wave into Mexico, but not nearly as far as the NAM.

The RGEM only goes to 48hrs, but it will be well north with the southern wave...especially compared to the NAM. This run likely wouldn't dig the southern wave too much, with the jet streak rounding the base of the trough already...compared to the NAM which has the jet streak on the backside of the trough, leading to the further digging. RGEM vs NAM...Might have to click it for it to loop.

Very true, but at random times we've seen the NAM hit the correct idea in the extended. We'll see how the rest of the 0z's come in.

If anyone thinks today's 12z UKMET was south, just wait till you see the 0z NAM... By 84hr, the northern wave is already entering the northern Great Lakes, while the southern wave is digging south into Mexico.

What? No model goes negative tilt until after it leaves the region, and the ECMWF is fairly E-W overall with the snowfall axis until OH on east.

GFS definitely took a step. Northern wave a bit faster, southern wave a good deal faster and further NE eventually, which lead to earlier phasing.

For those on the north end of the storm looking for a bump north, those looking for a cutter, or the historic-like 0z ECMWF run to occur... The one big negative I see that I didn't see before is that the main PV over the Hudson actually gets dragged east by a big storm around Greenland...just as the northern stream wave is diving south around the PV...which pulls the wave more the the east as well. One of the big reasons I believe the 0z ECMWF was a huge run is that the northern wave was faster and the PV was centered further west early on. This combination allowed the northern wave to dig more before sliding more easterly, allowing for some phasing earlier. Placement of the southern wave is key as well. There is good agreement on it coming onshore in N. CA and diving SE, with the base of the trough down into El Paso eventually. After that what is needed is key timing, as well as the wave closing off further north. The 0z ECMWF also had this occur and what was aforementioned with the northern wave, which helped lead to the big run. The lead minor wave on Wed/Thur will be fully sampled for this evenings runs. The south and northern wave will be well sampled by Thur evenings runs, and even more so after.

Just off of the second storm alone.

ECMWF, like the GfS, with another big dog for the following system. 24”+ across the Chicago area. .

That system on the GFS next week has snow in Chicago for 2 3/4 days. 15-20” that run. Would put back to back big dogs in play. .

Max snowfall that run was nearly 40” around Lima, OH. .

ECMWF could realistically still get better. It had absolute perfect timing of the northern and southern stream. The only issue is the southern stream gets strung out, which prevents deepening, a cut NE, and likely an even greater solution. Even without that, that was a big run for a big portion of the sub-forum. .

Last weekend was definitely not a long duration WAA event.

Looks like an extended on/off period of FZDZ and SG possible around here, from this evening into Wednesday morning.

Not gonna see any real sampling until Thursday.

I'm intrigued about this period...but there are some fail points. The first potential issue is if that lead wave on Wed/Thur continues to show up in a more organized way, which could lead to a less favorable environment (such as lower heights) for this main system to follow. The second potential issue would be lesser phasing or a total missed phase between the northern and southern stream waves for this main system. The third potential issue would be how far north/south the southern wave comes through the West. The final potential issue would the placement of the PV over Canada, and if it ends up further north or south. So while I can see a big dog happening with 12"+ amounts somewhere, I could also see a weaker/unorganized system way south as well. Edit: Another issue is also placement on northern stream, coming around the PV.

Finished with 2.5" at ORD and here.

I was thinking 6-9" for that area, and they're in the lower end of that range. So I don't think the did too bad overall.

I know, I just gotta get my shots in.